50 



deposition, this variation should be diminished. Processes that 

 bioturbate the sediment, such as sediment ingestion and excretion by 

 worms, blur the stratigraphic record of some sediment markers such as 

 radioactive isotopes or pollen profiles. These processes are relatively 

 unimportant in altering the eelgrass record because eelgrass seeds are 

 too large to be ingested by most deposit feeders. 



The rates of seed deposition, sedimentation rates, depths of 

 deposition markers, and photograph documentation are all consistent with 

 the interpretations given here, but additional dating methods should be 

 employed to verify actual dates. Nonetheless, these results demonstrate 

 eelgrass populations in each bay have shown sizable fluctuations in the 

 past, and that some of the trends are regional. Some of these 

 fluctuations like the wasting disease of 1931-32 appear clearly in 

 depositional record. Furthermore, reports of declines prior to the 

 wasting disease are substantiated because all the cores show a decline 

 around the turn of the century. If sedimentation rates were similar 

 prior to the wasting disease, as after, then the declines in each bay 

 most closely match the 1908 eelgrass decline in New England reported by 

 Cottam (1934). It is plausible that sedimentation rates prior to the 

 disease were lower, because the frequency of intense storms increased 

 after 1930 (Aubrey and Speer, 1984; Zeeb, 1985), which could have also 

 increased sedimentation rates. If so, then these declines coincide with 

 the 1894 decline reported by Cottam (1934) . 



The two bays with evidence of nutrient loading effects (Waquoit 

 and Apponagansett Bays) show eelgrass declines that are well documented 

 in the photographic and sedimentary record. Therefor, the use of 



